The present invention is directed to cooking thermometers and is particularly directed to electronic thermometers for cooking candy and fried foods to exacting temperatures.
The utilization of a reliable, accurate thermometer is essential for successfully cooking candies and fried foods. When cooking certain types of candy, such as fudge, caramel, taffy, nougats, or hard candy such as brittles, or lollipops, it is critical that the sugar in the candy be formulated into stages known as thread, soft ball, firm ball, hard ball, soft crack and hard crack. As used herein, and as is well known to those skilled in the art, the above-mentioned stages refer to the concentration of the sugar once the water has been boiled off and the sugar melts and breaks down. Previously, the terms were associated with how the sugar would react with ice water. Today, however, the preferred method for checking the stage of the sugar is to check the temperature of the sugar. The temperature range for each stage is very specific. As such, it is critical that the sugar is heated to, but does not exceed, a relatively small temperature range. For example, sugar heated to the stage known as soft crack (used for taffy) must be heated to, but not rise above, a temperature range of 270-290xc2x0 F. On the other hand, sugar heated to the stage known as hard crack (used for brittles) must be heated to a temperature range of between 300-310xc2x0 F. If the cooking temperature of the sugar exceeds the preferred temperature for the particular type of candy being prepared, the quality, texture and/or taste of the candy rapidly diminishes.
The requirement that products be cooked to exacting temperatures is equally true for foods that are fried in oil, such as fried chicken and french fries. Fried foods that are not cooked to the correct temperature will taste greasy. On the other hand, fried foods that are cooked at excessive temperatures will be overcooked. The preferred cooking temperature range for fried chicken is approximately 350-364.9xc2x0 F., while the optimum cooking temperature range for sea foods is approximately 365-372.9xc2x0 F. Other fried foods have other temperature ranges that must be met with exacting standards.
One known candy and oil thermometer includes an elongated thermometer tube and a graduated scale fastened to the thermometer tube. The tube and the graduated scale are placed in a protective sleeve that is closed at both ends. The thermometer tube has a bulb that is fastened to the lower end of the protective sleeve by a mass of solder commonly called a tin anchor, usually comprising 50% tin and 50% lead. The tin anchor serves to provide good heat transfer between the outer protective sleeve and the thermometer bulb and also secures the thermometer to the protective sleeve.
Over the years, there have been many improvements in candy and oil thermometers. For example, U.S. Pat. No. 3,636,770 to Chaney discloses a candy thermometer in which the tin anchor is eliminated for reducing the manufacturing cost of the thermometer. In Chaney, the thermometer tube and the graduated scale are thermally coupled to one another by providing a resilient member that exerts a downward force on the graduated scale to retain a bulb of the thermometer in close contact with the bottom end of a protective tube that surrounds the thermometer.
Although the above-mentioned thermometers have proven to be somewhat effective in accurately measuring temperatures when cooking sugar to make candy and when heating oil to fry foods, there remains a need for improved thermometers for monitoring temperatures when making candies and frying foods in oil. Such thermometers should preferably include prompting mechanisms for alerting individuals and chefs when the desired temperature range has been reached. Such improved thermometers should also provide one or more indicators (e.g. visual and audible) that the desired temperature has been attained.
Certain preferred embodiments of the present invention disclose an electronic candy and oil thermometer including a housing, a temperature sensing probe projecting from the housing, a visual display such as a liquid crystal display (LCD) provided in the housing for displaying unique visual indicia associated with a plurality of different food types, a control interface provided in the housing in communication with the visual display, and a controller in communication with the temperature sensing probe, the visual display and the control interface. The controller preferably includes operating protocols and a memory for storing temperature ranges for the candy cooking stages and for fried foods. A control interface is provided on the housing and in communication with the controller for selectively activating either a first of the operational protocols for monitoring temperatures associated with the candy cooking stages or a second of the operating protocols for monitoring temperatures associated with the fried foods.
In preferred embodiments, the temperature-sensing probe projecting from the housing includes a rounded lower end. In other words, the lower end of the temperature-sensing probe is not sharpened to a point but has an obtuse or rounded end. In certain embodiments, the temperature-sensing probe includes a heat sensor at a lower end thereof, the heat sensor being electrically connected with the controller in the housing for transmitting temperature readings from the heat sensor to the controller. The housing includes the visual display, which in certain preferred embodiments is a liquid crystal display (LCD). The visual display provides a unique visual indicator for each of the food types provided thereon. The visual display may also include a temperature display area which displays the most recently obtained temperature reading. The temperature display area may also periodically display a final desired cooking temperature.
Preferred embodiments of the present invention are used for cooking various types of candy or for frying various types of food in oil. The candy/oil thermometer may be used to cook all types of candies. Preferred candies that may be cooked using the present invention include caramel, syrup, fudge, pralines, nougats, taffy, brittles, lollipops, flan, and caramel cages. Preferred foods that may be fried in oil using the present invention include french fries, potato chips, seafood, fish, vegetables and poultry.
The housing of the present invention may also include an audible signal indicator in communication with the controller for providing an audible signal when the optimal cooking temperature range for the selected candy stage or fried food has been attained. The housing also preferably includes the control interface having at least two data entry keys for selecting a particular type of candy cooking stage or fried food for which the temperature will be monitored. The data entry keys may also be used to select and set a final desired cooking temperature. The at least two data entry keys may include an On/Select key, and a Set key for selecting the candy cooking stage or fried food to be monitored or a final desired cooking temperature.
In operation, a chef will activate the electronic thermometer by depressing the On/Select key provided on the housing. The chef may selectively activate the operational protocols for the candy cooking stages and the fried foods by pressing the On/Select button. Each time the On/Select button is pushed, the controller will toggle back and forth between activating either the operational protocol for the candy cooking stages or the operational protocol for the fried foods. When one of the operational protocols is activated, the other operational protocol is deactivated. Thus, when the candy cooking stage operational protocol is activated, the fried food operational protocol is deactivated and vice versa. The chef may then depress the Set key one or more times to pan through the array of candy cooking stage or fried food choices displayed on the visual display. Once the desired candy stage or fried food has been highlighted on the visual display, the chef will preferably release the Set button on the housing, thereby selecting the type of candy stage or fried food being monitored.
When candy or fried food is cooked, the sensor at the lower end of the temperature sensing probe obtains temperature readings of the candy mixture or oil and transmits such readings to the controller within the housing. The temperature shown on the visual display is continuously updated to reflect the latest temperature reading. As the temperatures are recorded and relayed to the controller, the controller compares the latest sensed temperature to the temperature range for the candy stages or fried foods stored in memory for determining whether the temperature range for the selected candy stage or fried food has been reached. If the temperature range has been reached, the controller activates the visual display and/or audible indicator for the candy stage or fried food to produce a prompt signal discernable to a human. In other preferred embodiments, the housing may also include an audible signal-generating element such as a beeper, buzzer or speaker that is in communication with the controller. The audible sound-generating element preferably generates a sound such as a beep when the sensed temperature reading matches the optimum temperature range for the selected candy stage or fried food. Once the desired temperature range has been reached, the individual monitoring the cooking of the candy or fried food will preferably remove the cooked candy or fried food from the energy (e.g. flame). In other preferred embodiments, the energy level may be reduced so that the preferred temperature range is not exceeded. As a result, the final cooking temperature of the candy or fried food will not exceed the preferred cooking temperature range, and the housing will immediately generate a prompt signal when a preferred temperature range has been attained.
In certain preferred embodiments, a clip is secured to either the elongated temperature probe or the housing for securing the thermometer to a cooking instrument. In one highly preferred embodiment, a compression clip is secured to the elongated temperature probe. The compression clip preferably includes a clip portion securable over an edge of a cooking vessel and a compressible attachment flange secured to the clip. The compressible attachment flange has two wings that may be compressed toward one another, each wing having an opening, the openings being in substantial alignment with one another. The clip is preferably slidably attached to the probe by passing the lower end of the probe through the openings in the wings. The wings are compressed toward one another in order to slide the clip along the probe. When the clip is at a preferred height relative to the lower end of the probe, the wings are released whereupon they spring slightly away from one another for locking the clip in place along the length of the elongated probe. Although the present invention is not limited by any particular theory of operation, it is believed that providing a slidably adjustable clip will enable the lower tip end of the probe to be placed approximately 4060 mm from the bottom of a cooking vessel, thereby preventing the tip from contacting the bottom of the vessel. Such an event (i.e. tip touching bottom) could result in an incorrect temperature reading. Thus, the slidably adjustable clip enables the tip end of the probe to be placed in the liquid being heated, while maintaining the tip end out of contact with the bottom of the vessel. The slidably adjustable feature enables the temperature check to be used with vessels having different heights.
The electronic candy and oil thermometer also preferably includes a protective cover for selectively covering the visual display. The protective cover is movable between a first position in which the cover covers the visual display and a second open position in which the cover is moved away from the visual display so that an operator may observe the display. The cover is desirably made of a conductive material, such as stainless steel, that deflects heat away from the front face of the visual display when the protective cover is in the second open position. For example, if the thermometer of the present invention is placed in a cooking vessel overlying a gas flame, the protective cover will deflect the rising heat of the gas flame away from the front face of the visual display. Thus, the movable cover serves as a protective shield for protecting the visual display from damage due to heat or condensation. The protective cover is preferably hingedly connected to the housing so that the cover may swing between the first closed position and the second open position. The protective cover may be made of a conductive material such as stainless steel. In highly preferred embodiments, the lower end of the protective shield is hingedly connected to the housing and the conductive or protective shield is made of a stainless steel material. Preferred colors for the protective shield include silver. The housing is preferably made of a resilient plastic material. Preferred colors for the housing include the color white.
These and other preferred embodiments of the present invention will be described in more detail below.